1. Field of Invention
The present invention relates to a recording media processing device that reads magnetic ink characters while conveying recording media such as checks that are printed with magnetic ink characters one at a time through a media transportation path. The invention relates more particularly to a recording media processing device that has a function for evaluating the transportation state of the conveyed recording media, including media orientation and multifeeding.
2. Description of Related Art
Check processing devices for processing checks and similar instruments are one example of a recording media processing device that processes recording media printed with magnetic ink characters. In stores as well as banks and other financial institutions, checks, promissory notes, and other check-like instruments received from customers are processed by a check processing device to read the printed magnetic ink characters, image the front and back of the check, and handle transaction processing.
The check processing device reads the magnetic ink characters and images the front and back of the checks by means of a magnetic head and a image sensors as the checks are conveyed one by one through the transportation path. Two storage pockets are formed at the downstream end of the transportation path, checks from which the magnetic ink characters were read normally are discharged into a first storage pocket, and checks from which the magnetic ink characters could not be read correctly are discharged into a second storage pocket. See, for example, Japanese Unexamined Patent Appl. Pub. JP-A-2004-206362.
Multifeeding, in which a plurality of checks are conveyed together overlapping each other, also occurs in check processing devices. When multifeeding occurs, the magnetic ink characters can be read from the top check in the stack that is conveyed with the read side against the magnetic head (also referred to herein as the “read-side check”), but the magnetic ink characters cannot be read from the checks on the other side of the top check (also referred to herein as the “multifeed-side check”). This results in a transaction error because the read magnetic ink character information does not match the check processed by the check processing device.
To solve this problem, Japanese Unexamined Patent Appl. Pub. JP-A-2005-225661 teaches a check processing device that has a multifeed detection means to detect multifeeding, and interrupts check transportation when multifeeding is detected. This multifeeding detection means detects the thickness of the check conveyed through the transportation path, and determines that multifeeding occurred if the detected thickness is greater than or equal to a predetermined thickness.
Some checks may also be inserted upside down with the top and bottom reversed and/or backwards with the front and back reversed from the expected normal orientation. In both of these situations the magnetic ink characters on the conveyed check will not pass the reading position of the magnetic head, and the magnetic ink characters cannot be read.
In order to quickly process checks that are not inserted in the correct orientation, we proposed in Japanese Unexamined Patent Appl. Pub. JP 2008-117040a check processing device that has an insertion direction evaluation means for determining the check orientation, and discharging checks that are loaded incorrectly into the second storage pocket without applying the character recognition process. If the change in the detection signal from the magnetic head is less than a predetermined level, the insertion direction evaluation means determines that the recording medium is inserted with the top and bottom inverted or with the front and back reversed. If the change in the detection signal is greater than or equal to the predetermined level, it compares the detection signal with the prestored signal patterns for magnetic ink character recognition to determine if the front and back of the recording medium are reversed.
When multifeeding occurs, however, the insertion direction evaluation means can make the wrong decision. For example, the orientation of the check on the read side of the multifed checks may be determined to be wrong even if the insertion directions of the checks on the read side and the multifeed side are correct. This decision error occurs when the magnetic head detects the change in the field strength produced by the magnetic ink characters of the checks on both the read side and multifeed side, and the detection signal cannot be verified with the signal patterns for magnetic ink character recognition.
If the check on the read side of the multifed stack is inserted with the top and bottom and front and back reversed but the check on the multifeed side is inserted correctly, the check on the read side may be wrongly determined to be inserted correctly. This is because the change in the field produced by the magnetic ink characters on the check on the multifeed side is also detected by the magnetic head, and this detection signal is compared with the signal patterns for magnetic ink character recognition.
If the insertion direction is incorrectly detected, the checks cannot be processed quickly even though the check processing device has an insertion direction evaluation means. The information printed on the read-side check and the information from the read magnetic ink characters will also not match, and the transaction process based on the read information will therefore also be wrong.
Because the check processing device has a multifeed detection means in addition to an insertion direction evaluation means, incorrect determination of the insertion direction can be eliminated if the check processing device is controlled so that multifeeding and the insertion direction are always detected together. However, check processing devices are generally configured so that whether multifeeding is detected and whether the insertion direction is detected can be controlled separately as needed by the user.
For example, check processing devices are also used to capture images of both the front and back of each check in order to save images of the front and back of each check as proof of check usage. Detecting the insertion direction is not necessary in such applications because the front and back images captured by the image sensors can be used regardless of the check insertion direction. In addition, if the insertion direction is detected based on the detection signal from the magnetic head even though magnetic ink character recognition is not applied, the speed of the check imaging process drops. This happens because the user selects controlling the check processing device to determine only multifeeding.